Jorge Vieira has constantly represented animals during his career. This facet is mainly related to his curiosity in prehistoric art and its symbolic systems of figuration. This interest was reinforced by the contact with the work of Picasso, which stimulated Vieira's cultural awareness concerning the value of primitive art and, above all, the origins of Iberian art. Within this framework, his preferences focus on an ancient and mythological world populated by powerful animals such as the bull, the bison, or the horse, represented in different poses and volumetrics.

This drawing recalls the series of lithographs - El Toro
, produced by Picasso in 1945. In that series, the Spanish artist visually dissects the image of a bull, starting with a naturalistic representation, and ending with the formal deconstruction of the animal. Like Picasso, here Jorge Vieira seems to (de)compose the bull by simplifying the main planes of its anatomy. The form is defined by sections, where the muscles of the animal's forelegs and hindquarters stand out, thus highlighting its strength and ferocity. The drawing is constructed from small lines that define the contours and simultaneously simulate the texture of the bull's hair. The same lines contribute to the modelling of the chiaroscuro, which is discreet but still enough to give volumetry to the composition. Despite its great formal simplicity, the composition is characterised by anatomical correctness and attention to detail.